willmarth



J- T. WILLMARTH.

Bolt Machine.

Patefjted Jany '16, 1855.

' IUNITED "STATES PAtrE ronFIoE.

JOHN T. WILLIQIARTH; OF NORTHBR'IDGE,.MASSAGHUSETTS.

DIE ron MAKING BOLTS. l

Specification of. Letters Patent No. 12,262, :dated January -16, 1855.

T 0 all whom it may concern:

Be it knownthat I, J NO. T. WILLMARTH, of Northbridge, in the county of. Worcester and State of-Massachusetts, have-invented a new and useful Improvementin the Manufacture of Bolts, of which'the following is? a full, clear, and exact description, reference being had tothe annexed-drawings, in 'which Figure 1 is a section through the machine with my improvements attached. Figs. 2, 3, 1 4E, and 5 detached views which will be here after referred to.

My improvements relate particularly to the formation of the head of the bolt, p're-i paratory to drawing down the'shank'there of. Iron bolts have been made of rods of the size of the sha'nkof the finished bolt, the head being formed'by upsetting the end of the rod. Such bolts are however weakest at a point which is required to be the strongest viz the junction of the head and shank. They have also been formed of rods of the size of the head of the finished bolt or slightly less, a sufiicient length of the rod being first drawn down upon one side of the head to form the shank; the bolt is then cut off and the head finished in suitable dies. A great defect of this method of forming the bolts is this: there being nothing but the strength of the operator to hold the bar up to the dies during the operation, it is continually worked backward, the head being constantly forced away from the dies, and unless the bar is v held up to the dies with exactly the same force each time, there will be a want of uniformity in the length of the bolts, rendering it necessary to put them through another operation to cut them to a length. It is also found that bolts thus made are liable to have the shank out of center with respect to the head. And fur-' thermore it is not found possible to attain an exact thickness of head by this process, for the operator in judging of the length of iron to be cut off to form the head is guided only Joy his eye.

To remedy these defects'is the object of "my present invention,'which consists in cutting away the iron simultaneously upon each side of the head, the iron so cut away being at the same time pressed out and partially drawn out, iron rods of the size of the finished bolt head'being made use of, the operation being. performed by suitably formed dies which will now be described.

' and 6.

through its whole depth to permit the escape.

provements are applied,- and thendescribing the details of my invention.

5 In the accompanying-drawings B is the bed piece of the machine which is firmly bolted or otherwise secured to the foundation timbers of the shop, and in which are secured .thelower dies a. The upper dies are .carried by the side pieces D of a vibrating frame which is constructed and operated as follows E are, side posts secured at the'bottom to l' the 'sidepieces D, and at the top to the cap piece F this frame is pivoted upon gudgeons G, one of which is'seen in dotted lines in Fig. 1 running in the boxes, H. r

L are eccentrics secured to the shaft- K andrunningv in the straps or housings M. These housings are grooved so as to slide freely up and down upon the side posts E. The shaft K is revolved in uprights rising from the base of the machine, its motion being regulated by the fly whe'el N. As the shaft K revolves the frame D, E, F, is vibrated upon its gudgeons G so as to bring the dies upon the opposite sides of the machine alternately into operation. These dies are arranged in pairs as seen in Fig. 1, their form and operation will now be described. g The upper'arrd lower dies a, a, are similarly constructed and are seen in section in Fig. 2, and in elevationin Fig. 4. Fig. 3 is a plan of the lower die. y is a groove through the center of the die which divides it into two portions 1 and 2 Fig. 2. Upon each side of this groove the die falls away in a curve or slant as seen in Figs. 1 and 2. At one end f they approach each other nearer than at the other f, for a purpose which will be presently made clear. In Figs. 2 and 4 these dies are seen as when nearest to each other they are secured in place when in operation by the screws 6 The bed piece B has a slot R of the scale. s

Operation: The frame hich carries the upper dies being vibrate as already described a bar of square iron of the size of the head of the finishedbolt or nearly so, is heated and enteredbetween the dies a a at the end f, 4 when they 'are at the greatest distance from each other, the distance to which the bar is protruded being regulated by an adjustable stop 8; as the'diesifa a: approach each other a portion of the bar enters the groove y, (Fig. 2) and the iron is cut away upon each side of it by the edges 11., n, and at the same time slightly compressed, the bar being constantly rotated thatthe action .ofthe dies'may be uniform upon all sides of it, and as the. operation proceeds itnis alsomoved toward the other end f of the dies, when the two jaws. ap. proach nearest to each otherand-the iron is thus gradually cut down upon eachside of the head, and the. iron, gradually squeezed out little by little and brought to the form represented atR in Fig. 2. The portion S of the barwhich is to form the. head of the bolt is left of its original size'and form, and the portion Z which is to form? the shank of. the bolt is made .toslightly approach its u1timatefo'rm.the bolt may now be completed by any suitable means. The two portions 1-2 of the'dies may be madeadjustable with respect to each other bymeans of the right andleft screws y, as seen in Fig. 5 r for the purposeof increasing or diminishing the thickness of the head.

The above method of forming theheads of bolts has manyadvantages over allother ,1 What I claim as methodswith whichI am'acquainted, among which are the following lst, the iron being operated upon, on both sides of the head at onoeg'the latteris-not' forced away from .the dies as is the case when it is operated upon'onoiie side of the head at a time, and thus a determinate quantity of iron is thrown into the shank ofeach bolt, and the necessity of cutting oii' the end of the latter to reduce the bolts. to a uniform length (is avoided. end; theiron being gradually cut awaytallaround-the head the. fibers of the out ofcenter with respect to the head as is often the case with bolt-s formed by other methods; 1 I to secure by Letters Patent. is

The dies a a constructed as described, or

in any: manner substantially equivalent thereto, for the-purpose ofoperating simultaneously upon both' sides' of the head as set forth, a

qvVitnesseszs 1 .HANNAH C. .TAYnoR,

JOHN TAYLOR.

my invention and desire I 

